Scientists hoping to bury our greenhouse gas problem

Rick C. Hodgin, 27th November 2007

Leeds (England) - Researchers at the University of Leeds are proposing that CO2 gases be dissolved into water, and then pumped miles beneath the surface of the Earth to be captured permanently in sandstone layers. The goal is to effectively offset "one of the planet's major contributors to climate change," that of CO2 gases generated by power stations.

The research was based on data collected over a seven-year period from a British Petroleum (BP) oil field in the North Sea. The report indicated that when oil production began to decline, BP began pumping seawater into the oil reservoir to increase the flow. As the oil was extracted, some seawater came up with it. That seawater was then analyzed to determine how easily minerals dissolved in the water. From this data, they were able to determine that sandstone layers have the ability to dissolve far more liquid must faster than was previously thought. In fact, within one year, nearly all of the pumped in seawater had been dissolved into the rocks.

According to the research, this kind of permanent storage mechanism would be required if the carbon dioxide dissolved into water was to be removed in a stable way. Several previous studies have indicated that deep burial within the Earth is a possible solution to address greenhouse gas emissions. In fact, there is one field operating today at Sleipner, a Norwegian section of the North Sea. However, until recently the conventional wisdom was that it would take 100s to 1000s of years for the CO2 to be completely dissolved, allowing for the possible future escape.

Armed with this new data, the process will likely be gaining renewed worldwide attention. In the UK, for example, Prime Minister Gordon Brown has recently announced a large expansion of energy from renewable sources. He's also launched a competition to build one of the world's first true carbon capture and storage plant.

Stephanie Houston, a PhD student at the University of Leeds, contributed significantly to this endeavor. Her work was funded as part of an Industrial Case Studentship by the Natural Environment Research Council and BP. Professor Bruce Yardley, Institute of Geological Sciences, supervised her work.